Turbo jet and ram jet engines have been combined in aircraft which are designed for supersonic flight. For example, the U.S. Pat. No. 2,944,764 of Lane et al. discloses an aircraft with a plurality of engines wherein the engines are partly turbo jet engines and partly simple combustors forming a ram jet system. A more recent U.S. Pat. No. 5,058,377 of Wildner discloses a turboramjet engine. As disclosed by Wildner, a turboramjet engine is provided with a ram pressure air duct shrouding the basic turbo jet engine in an annular manner. When the ram jet operation is disconnected, the ram pressure air duct, while at the same time intake air is released into the basic engine, is blocked off with respect to the supply of ram pressure air. A ring slide is provided which is axially adjustable to always be opposite a body which blocks the ram pressure air duct when the inflow cross-section of the basic engine is unblocked and unblocks it when the inflow cross-section is blocked.
A turbo jet/ram jet propulsion system in accordance with the present invention provides improved performance by efficiently using the waste heat from the turbo jet engine to produce ram jet thrust. This efficiency is achieved by the total integration of the turbo jet and ram jet principles into the flow design which will be described hereinafter.